Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.
Common duplication problems, and corresponding solutions are:
| 1 | <?php  | 
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| 7 | View Code Duplication | class CreatePaymentSystemParamsTable extends Migration  | 
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| 8 | { | 
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| 9 | /**  | 
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| 10 | * Run the migrations.  | 
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| 11 | *  | 
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| 12 | * @return void  | 
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| 13 | */  | 
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| 14 | public function up()  | 
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| 25 | |||
| 26 | /**  | 
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| 27 | * Reverse the migrations.  | 
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| 28 | *  | 
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| 29 | * @return void  | 
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| 30 | */  | 
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| 31 | public function down()  | 
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| 35 | }  | 
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| 36 |